The following lines continue the declaration of the public static main
method. The code file for the sample is included in the mqtt_essentials_gaston_hillar_04
folder, in the Java01/src/Main.java
file:
mqttAsyncClient.setCallback(new MqttCallback() { @Override public void connectionLost(Throwable cause) { cause.printStackTrace(); } @Override public void deliveryComplete(IMqttDeliveryToken token) { } @Override public void messageArrived(String topic, MqttMessage message) throws Exception { if (!topic.equals(topic_for_led01)) { return; } String messageText = new String(message.getPayload(), "UTF-8"); System.out.println( String.format("Topic: %s. Payload: %s", topic, messageText)); } });
The code calls the mqttAsyncClient.setCallback
method with an anonymous subclass of the MqttCallback
class as an argument. The setCallback
method requires...